Electrohydraulic coal-mining system

摘要

A mining system comprises a laterally deflectable segmented conveyor extending longitudinally along a longitudinal face from which material is to be cut, a mining machine displaceable longitudinally along the conveyor and engageable with the face to cut material therefrom and deposit in the conveyor, and a longitudinal succession of support frames each having a respective actuator connected to a respective segment of the conveyor and each also having a respective a respective retractile roof-engaging flap. The process of this invention comprises bracing the frames and conveyor in a safety zone immediately adjacent the mining machine against the roof with their flaps retracted. The machine is advanced in the safety zone while cutting the face in the safety zone, and the flaps of the frames in a zone immediately downstream of the safety zone are sequentially retracted and the flaps of the frames in a zone upstream of the safety zone are sequentially advanced. The number of frames in the upstream and downstream zone is determined by the stability of the material of the mine roof. The conveyor segments are meanwhile pushed toward the face by extension of the actuators of the frames in a second zone immediately upstream of the upstream zone and the frames are themselves drawn toward the face by contraction of the actuators of the frames in a third zone immediately upstream from the second zone.